John a



(No Model.)

J.`A.SVEDBER3.

BOILER.

No. 363,733. Patented Aug. 23, 1337.

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Nrrnn STATES.

Ars Fries.

JOHN A. SVEDBERG, OF LOUDOUN, VIRGINIA.

BOILER.

SPECIFICATION forming part of Letters Patent No. 368,739, dated August23, 1:88a.

` Application tiled August28,1886. Serial No.212,058. (No model.)

To all whom t may concern.-

Be it known that I, JOHN A. SVEDBERG, having declared my intention ofbecoming a citizen of the United States, residing at Loudoun, in thecounty of Loudoun and State of Virginia, have invented certain new anduseful Improvements in Boilers, of which the lfollowing is aspeciiication, reference being had therein to the accompanying drawings.

My invention relates to improvements in what are usually termedcoil-boilers 5 and the object is to produce a boiler having a largeamount of heating-surface in proportion to grate-surface, contained in avery small and compact space; also, that all the joints, as well as thetubes, are easily accessible; also, that any of the coils can be readilyrepaired, removed, and replaced when necessary. Furthermore, that a freeand regular circulation of water can be obtained; sediment is not liableto collect in the coils, but deposited in a mud-drum formed in the lowerpart of the boiler, and can be easily blown out, when desired; and,finally, that it can be produced at a very small expense.

The invention consists of a central steamand-water chamber, to which aseries of coils are connected at their upper and lower ends, andcommunicate with the steam-andwater space. They are surrounded by acasing and placed over the furnace and grate bars in such manner thatthey are entirely surrounded by the gases and products of combustion.

It also consists in providing means to afford access into the drum andto the ends of the coils to expand them in place, as well as tofacilitate the removing and replacing thereof, when necessary.

It further consists in providing means to facilitate the blowing out orcleaning of the coils or mud-chamber from sediment, whenever desired,and it finally consists in the construction of certain details andarrangement of parts, as will be more fully described hereinafter, andspecifically pointed out in the claims, reference being had to theaccompanying drawings and the letters of reference marked thereon.

Like letters indicate similar parts in the different figures of thedrawings, in which@ Figure 1 represents a horizontal section of myimproved boiler or steam-generator. Fig. 2 is a vertical cross-sectionof the same, showing one series of coils. Fig. 3 is an enlarged detailView.

VIn the drawings,-A represents a steam-and-4 water chamber, ofcylindrical, conical, or other suitable shape, to which a series oftubular coils, B, are secured at their upper and lower ends,communicating with the steam-and-water space,and said coils may beusually secured in place by expanding their ends. The coils are arrangedaround the periphery of the central chamber, A. The upper end ofthischamber is closed by a removable man-hole plate, A,to gain access to theinterior, and the lower end of said chamber is attached to a pipe ortube, a, which in turn is secured to a casting, a', forminga mud-drum orsediment-chamber, and bolted or riveted to the bottom of the boiler. Inthe upper part of the pipe a is inserted a tube,l, of smaller diameter,supported on two or more lugs or brackets,m, and provided with shortpins or studs a at its lower end, by which the tube is held in a centralposition, so that the annular space formed around the tube lis ofuniform size. This tube permits the Water from the chamber Ato freelydescend through it, while the annular space permits a free circulationof water upward. It also prevents tilling up of the pipe a with sedimentand mud. Said casting c has a nozzle, to which the blow-off pipe c isattached, and a removable plug or cap, a, for cleaning. The feed-pipeffor the feed-water enters the chamber A near its upper part and descendstoward the bottom.

The chamber A and coils B are surrounded by a casing, C, which isprovided with a jacket containing asbestus, ashes, or othernon-conducting material to prevent radiation, and it forms at its ripperpart the'uptake h, to which the smoke-stack z' is attached.

The coils B are preferably secured in place in the following manner: Ashort piece of tube, B', is irst screwed into the shell of chamber A andexpanded, its end is screwthreaded, as seen in Fig. 3, suitablecouplings, b, are then attached to said piece B', and the -coil Bsecured to the other end of 'the coupling, which is provided with arightand-lefthand thread. This facilitates the ready re- IOO moval andreplacing of the coils. The coils may, however, be secured in any othermanner, if desired.

The furnace F is placed immediately below the chamber A and coils B, andis provided with the grate or grate-bars D and furnacedoor d, and belowthe grate is arranged the ashpit E, having a suitable ash-pit door, e.

Above the upper end of the coils B 'is placed a perforated diaphragm, b,to prevent foaming, and the steam pipe g is attached to the chamberAabovesaid diaphragm. A vertical pipe, c, forming a communication withthe steam-pipe g and blow-off pipe a, is provided with a gage, g, forindicating the height of water in boiler. All the pipes are necessarilyprovided with suitable valves, (not shown,) and a safety-valve can beattached to the T-pieee r on the steam-pipe g.

The casing Gis preferably made in two parts, and is bolted togetherbybolts passing through the angle-irons o, or suitable flanges for thepurpose. The uptake h may also be made detachable, if desired, andv ashield, p, is placed over the man-hole plate A to protect it and itspacking from the act-ion of the heat.

The height of the steam-and-water chamber can be varied as desired, andthe upper part serve for drying or superheating the steam,

im* i and the general dimensions of the boiler can be variedv to suitdifferent circumstances and purposes. If desired, additional coils maybe employed by interlaeing them between the coils shown, and they may bearranged in a staggering manner, or several series of coils may bearranged above each other, and they may be then placed in the mannershown in dotted lines in Fig. 1.

If desired,the tubes B may be of larger diameter than the coils B, andcouplings b', having different sizes of screw-threads to suit thediameters of the tubes B and coils B, may be then employed. The tubes Bmay be made a permanent fixture of the shell by expanding them afterthey have been screwed in place, and this also prevents them fromturning. In very large boilers the tubes B may be dispensed with and theshell flanged out and screw-th readed to receive the couplings b.

It will be readily perceived by engineers and others skilled in the artthat the advantages obtained in this boiler are numerous, and among themmay be cited that .a large heatingsurface in proportion to grate-surfaceis obtained, the parts are readily accessible, the water has a freecirculation and is unobstructed by `joints, and the liability of formingscale is thereby obviated, and the sediment which forms the scale can beeasily removed by blowing out, and the entire ,boiler is very compactand inexpensive. By the rcduction of pipe a the `fireon the grate isreadily accessible and can be easily reached..

Having thus described my invention, what I claim, and desire to secureby Letters Patent, 1s

l. A boiler having a central chamber, A,con nected by a pipe, a, ofreduced diameter, to a mud-drum, t,iu combination with a series of coilsand a casing, arranged substantially as specified.

2. In a boiler having a central chamber, A, and a series of coilsconnected thereto, t'he pipe a, of reduced diameter, containing acirculating-tube, Z, arranged as and for the purpose set forth.

3. In a boiler having a central chamber provided with a pipe, a, ot'reduced diameter, containing` a circulating-tube, Z, arranged as shown,and for the purpose set forth.

4. In a boiler, a central chamber and a series of coils connected to theupper and lower ends of said chamber, which communicates witha mud-drumby a central pipe provided with a circulating-tube, all arrangedsubstantially as set forth.

5. A boiler consisting of a central chamber and a series of coilsconnected'thereto, and inclosed in a casing, a mud-drum connected tosaid chamber by a pipe of. reduced diameter, provided with a suspendedcirculating-tube,

and the feed and steam pipe, all substantially series of coils supportedon a pipe of reduced diameter passing through the grate and secured to apoint below said grate, so that the upper part can freely expand andcontract, substantially as set forth.

7. In a boiler having central chamber, A, coils B, furnace F, ash-pit E,and inclo'singcasing C, infcombination with a pipe, a, muddrum a',blow-off pipe-a, steam-pipe g, and communicating-pipe k, provided with awatergage, all substantially as set forth.

8. Aboiler consisting of central chamber,A, series of coils B,inclosing-casing-C, forming furnace F, and ash-pit E, with grate-bars D,in combination with a mud-drum, a', pipes a a, and vertical pipe lo,connected to steampipe g,A and a feed-pipe, f, all arranged as shownand'specitied.

9. In a boiler having acentral chamber provided with a man-hole plateprotected by a shield, p, a series of coils arranged circumferentially,a mud-drum, communicating-pipes, as shown, and an inclosing-casing, allas set forth.

In testimony whereof I affix my vsignature in presence of two witnesses.

FRANCIS C. BAKER, A. M. l?. Mixscniunvnn.

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